Process for preparing color images

ABSTRACT

Color development in the presence of oxidatively coupling quinolone sulphonylhydrazone couplers to improve the absorption characteristics of the cyan dyes produced and reduce the undesirable blue fog in the cyan dye layer.

United States Patent Inventors Appl. No. Filed Patented Assignee Priority Jan Jleken Hove;

Wilhelmus Jansens, Aarschot; Marc Godiried Mennens, Wilrijk, all of Belgium 8,525

Feb. 4, 1970 Nov. 23, 197 l Gevaert-Agia N.V.

Mortsel, Belgium Feb. 4, 1969 Great Britain PROCESS FOR PREPARING COLOR IMAGES 12 Claims, 2 Drawing Figs.

US. Cl

20 40 so a0 70a l] Int. Cl G03c 5/50 [50] Field of Search 96/22, 54, 73,55, l00;960/288 [56] References Cited UNlTED STATES PATENTS 3,293,032 i2/l966 Jaeken et al. 96/22 Primary ExaminerNorman G. Torchin Assistant ExaminerAlfonso T. Suro Pico Attorney-William J. Daniel ABSTRACT: Color development in the presence of oxidatively coupling quinoione sulphonylhydrazone couplers to improve the absorption characteristics of the cyan dyes produced and reduce the undesirable blue fog in the cyan dye layer.

I I I I an I l l l a P-ATENTEDuuv 23 ml SHEET 1 BF 2 FIG. 7

PROCESS FOR PREPARING COLOR IMAGES The present invention relates to a process for preparing direct positive color images, to hydrazone compounds of use in said process and to photographic materials containing such hydrazone compounds.

in US. Pat. No. 3,293,032 a process for the preparation of direct positive color images is described, which process comprises the steps of l imagewise exposing a photographic element comprising (a) at least one water-permeable layer which contains light-sensitive silver halide grains, (b) a color coupler in effective contact with said silver halide grains, said color coupler being capable of forming on development a dye which by treatment with a strong acidic solution can be converted into colorless products, and (c) a compound in effective contact with said color coupler, said compound being capable of forming an acid-resistant dye by oxidative coupling with said N-NHSO R color coupler (2) developing the photographic element in a color-forming developer, (3) treating the photographic ele- MO;,S

ment in an oxidative bleaching bath, (4) treating the photographic element in a strong acidic solution, and (5) fixing the photographic element no later than after step (4) but not be- N fore step (2), to produce colorless reaction products at the places where development occurred and a positive color image of the object to be reproduced as a result of the oxidawherein:

tive coupling at the nondeveloped areas of the photographic Ar stands for aryl including substituted aryl e.g phenyl and element where color coupler is still present after the developphenyl substituted by alkyl including substituted alkyl,

ment. aryl including substituted aryl, aralkyl including sub- According to a preferred embodiment of the process of the stituted aralkyl, cycloalkyl, carboxyl or sulpho in acid or' above United States patent specification a photographic mulal m, h g a y c ng Substituted yi tilayer material is used which comprises a red-sensitive, a aryloxy including substituted aryloxy, alkylthio including green-sensitive and a blue-sensitive silver halide emulsion substituted alkylthio, arylthio including substituted layer each of said layers containing a color coupler capable of arylthio, alkylsulphonyl including substituted alkylforming on development a quinone-imine or azomethine dye sulphonyl, arylsulphonyl including substituted arylwhich by treatment with a strong acidic solution can be transsulphonyl, nitro, amino including substituted amino,

formed in colorless product, the red-sensitive emulsion layer heterocyclic residues, etc: 3

also containing a compound which is capable of forming an R stands for alkyl including substituted alkyl, aryl including acid-resistant cyan dye by oxidative coupling with the color substituted aryl, aralkyl including substituted aralkyl or coupler present in that emulsion layer the green-sensitive amino including substituted amino,

emulsion layer also containing a compound which is capable R, stands for alkyl including substituted alkyl such as methyl of forming an acid-resistant magenta dye by oxidative and chloroethyl,

coupling with the color coupler present in that emulsion layer M stands for hydrogen or an alkali metal atom such as and the blue-sensitive emulsion layer also containing a compotassium, sodium.

pound which is capable of forming an acid-resistant yellow The oxidatively coupling hydrazone compounds cordye by oxidative coupling with the color coupler present in responding to the above general formula can be prepared as is that emulsion layer.

It has now been found that the absorption characteristics of the cyan dyes produced as described and claimed in the above United States patent specification can still be improved as regards the undesirable side-absorption in the blue and green re- 5 gion of the spectrum by the use of novel oxidatively coupling quinolone hydrazone compounds. Moreover, the undesirable blue fog produced in the layer containing the cyan dye formed by means of the oxidatively coupling compounds listed in the above United States patent specification can be reduced or eliminated by the use of these novel quinolone hydrazone compounds.

The quinolone hydrazone oxidatively coupling compounds according to the present invention can be represented by the following general formula:

illustrated by the following reaction scheme:

lzwc. (A) n (|)H 11,): F018 P0011 F015 or $001 Ar 2 Ar N N I-INHSO,R|

Ar R:

wherein R R and Ar have the same significance as above and X"=" stands for an acid radical.

The quinolones (B) prepared by a Conrad-Limpach reaction as illustrated by the above reaction scheme are sparingly product was recrystallized from 1.5 liter of ethylene glycol monomethyl ether taking care that the mixture did not boil since otherwise the active chlorine atom of the quinoline would react with the ethyleneglycol monomethyl ether.

soluble compounds having a melting point almost ever lying 5 Yield; 195 g P above 260 C. The qunolones (B) are converted into the Melting Point chloroquinolones (C) by means of phosphorus oxychloride or y 'p y 1'4-chlol'o'fluomsulphonylquinolinium thionyl chloride whereupon by quaternization compounds methy! Sulfata (D), having an unsharp melting point, are formed. The 100 8( mole) of 'p y sulphonyl hydrazones E are f d b reaction f 10 fluorosulphonylquinoline and 88 ml. (0.93 mole) of dimethyl pounds (D) with the appropriate sulphonylhydrazide whereusulphate (distilled and dried on molecular sieves) were heated Po" the fl l h group in the 6 position is ifi d for hours at 85 C. At the beginning of the reaction the mixthus forming the oxidatively coupling sulphonylhydrazone ture was stirred as long as possible. The SOild product formed compound, the melting point of which generally lies above 1 5 was wahed w ether and further used as Such C Melting point: 180 C.

The following preparation illustrates in detail how the sulfolmethyl2Phenyl'6fluMosulphonyl'qumolone'4n'hex nyl hydrazone compounds according to the present invention adecylsulphonyl hyldrazone are prepared Two-hundred thirty-five gram (0.525 mole) of l-methyl-Z- phenyl-4-chloro-6-fluorosulphonyl-quinolinium methyl Preparation 20 sulphate and 168 g. (0.525 mole) of n-hexadecyl sulphonylhydrazide were refluxed for 4 hours in 2 liters of chloroform. 1'[HPfluorosulphonylamlmo and ethyl ester The solvent was thoroughly removed by evaporation at a max- 175 (1mm? of benzoylacenc and ethyl ester 175 imum temperature of 60 C. The residue was dissolved in 500 (lmole) of P' 'f 9 and 3 f ml. of boiling ethanol and the solution formed, after addition polyphosphonc were heated with Sun-"Hg at of 200 ml. of pyridine, was poured into 8 liters of water. The the mixture became homogeneous- The mlxtul'e was Piaced precipitate formed was filtered by suction and recrystallized for 5 days in a vacuum drying oven (50 C./25 mm. Hg.) over from acetonitri1e sulphuric acid. The precipitate formed was washed with 250 Yi l 257 79 percent) ml. of methanol and then with water until the product was suf- 3 0 M l i i 158 C f y acid flea 6. l-methyl-2-phenyl-6-sulphoquinolone- 4n-hexadecyl- Yield: 225 g. (64.5 percent). sulphony] hydrazone Melting Point! C Three-hundred ten gram (0.5 mole) of l-methyl-2-phenyl-6 P y y y' p y q -fluorosulphonylquinolone -4n-hexadecylsulphonyl hydrazone 260 mole) of l -(P' P "Y 3 5 were dissolved with heating in 4 liters of acetone. While stiracid ethyl e er wer rapidly addCd at 2 n with Stirring ring and introducing a nitrogen current a solution of 64 g. L6 to 2.5 liters of diphenyl ether. Stirring was continued for 10 mole) f odium h droxide in 300 ml. of water was added minutes whereupon the reaction mixture was allowed to cool. dro wise. The mixture was refluxed for 1 hour and cooled The precipitate formed was filtered by suction and washed whereupon the precipitate formed was filtered by suction and with ether. 40 washed with a mixture of acetone and water (:5 The Yield: 205 g. (91 percent). product was recrystallized from acetic acid and washed with Melting point: 260 C. methanol. 3. 2-phenyl-4-chloro-6fluorosulphonylquinoline Yield: 275 g. (89 percent). 205 (0.68 mole) of 2-phenyl-4-hydroxy-6fluorosulphon- Melting point: 260 C. q and 136 mole) of Phosphorous 45 in the following table are listed compounds corresponding ychloride heated for 2 hours at After having been to the above general formula, which were found to be particucooled the reaction mixture was pour in Th larly suitable for use in accordance with the present invention precipitate formed was filtered by i n n Washed and which were prepared as described in the above preparacompletely acid free with water and sodium acetate. The tion.

$55133? (nm.) of the cyan dyes fonned Melting point according to of inter- Example 2 mediate hereinafter product (With colour C.) coupler) Compound Ar R1 R; (C) (E) 1 2 1 Q C15H3a CH3 128 158 663 660 2 C 5Ha; CH; 152 167 660 662 3 CH3 CmH;; CH; 123 155 653 648 4 CH3 -C1H33 CH3 130 665 660 Absorption maximum (nm.) of the cyan dyes formed Melting point according to of inter- Example 2 mediate hereinafter product (With colour C.) coupler) Compound Ar R| R: (C) (E) l 2 26 OCH: C qH3:i -CH3 216 110 662 U S OaNB.

27 C H CH; 210 165 666 '54 28 SOzH -CH3.\ -CH3 168 190 664 666 29 $03K -CH; CH 97 150 680 664 3 Q (CH7)n-CH3 -CH; 128 152 663 66 31 5 NH; CH3 128 180 663 660 SOzCmHa:

32 Q COOH -CH; 128 I38 654 '0Cm za 33 Q 0 CuHa; -CH; 128 167 664 65 C O OH 34 CH; O CmH CH; 130 200 665 653 C 0 OH 36 O CmHaa CH: 220 230 658 660 COOH I COOH 36 0 CiuHaa CH: 149 660 668 CH5 Q C O OH 37 S Q 0 CmHaa CH3 186 658 655 Q Q I C 00H 38 0 CmHa; CH; 207 220 660 655 COOH 39 O C "H33 CHa 190 210 654 650 COOH Absorption maximum (nm.) of tho cyan dyes formed Melting point according to inter- Example 2 mediate hereinafter product (With colour C.) coupler) Compound Ar R1 1 2 ?H; 0 (Juli CH; 172 176 665 665 I C 0 0H 41 1710; CH; CH; 92 120 662 660 42 CH; -CH; 88 120 660 660 iu zz Q-owm; Qoomcoon 44 CH 88 186 660 658 Qo CrsHaz OH 3 C 0 0H 45 f E CmH CzHr 128 135 657 551 46 Q C H a CzHqCl 128 120 646 642 47 16h C H C H; 146 166 668 666 ii 4 z 8 C H CH 166 160 668 662 49 07H; CMHH CH; 155 168 66 660 mHza CH; 142 140 669 664 Qoomomoom Color couplers preferably used in conjunction with the quinolone hydrazone compounds according to the present invention to form cyan dyes on oxidatively coupling therewith are colorless color couplers capable of forming on color development with aromatic primary amino developing agents e.g. N,N-diethyl-p-phenylene diamine, indophenol or quinone-imine and indo-amine dyes which by treatment with a strong acidic solution can be converted into colorless products.

Among these color couplers there may be mentioned phenol and a-naphthol compounds, which in the common color development with aromatic primary amino developing agents form cyan, indophenol or quinone-imine dyes that are not completely acid resistant, and m-acylamino-N,N-dialkylanilines and a-naphthylsulphamoyl compounds, which form on color development with aromatic primary amino developing agents indoamine dyes that are also not completely acid resistant.

Though, in conjunction with the quinolone hydrazone oxidatively coupling compounds according to the present invention the a-naphthol color couplers, for which there can be referred to the above US. Pat. specification and the patent literature referred to therein, to Belgian Pat. Nos. 548,880 and 596,509 and to United Kingdom Pat. No. 1,104,729, are preferably used, the a-naphthylsulphamoyl and m-acyl-amino- N,N-dialkylaniline color couplers corresponding to the following general formulas having also been found to be particularly suitable:

rendering the compound fast to difiusion having from five to twenty carbon atoms in straight line. Examples of color couplers corresponding to the above were mul re NHSO 0 CmHn OOH (b) v (Julius ooorr (c) C OOH NHO o-(omm-om (d) soma @IflrsoQ-mro o- OCiuHzs (e) 0 io aa 0 n aa a):N NHC O- (8) O CmH'aa (C1H5)2N NHSOr- C O OH The oxidatively coupling quinolone hydrazone compounds according to the present invention and the color couplers used in conjunction therewith are preferably incorporated in the photographic material in a form fast to diffusion. For that purpose they contain in their structure a long aliphatic carbon chain, preferably a carbon chain having from five to twenty carbon atoms in straight line.

In the preparation of a light-sensitive color element for producing direct positive color images according to the method of the above U.S. Pat. specification, the color coupler and quinoline hydrazone compound are preferably incorporated into a light-sensitive silver halide emulsion layer of the said element. They may however, also be added to the composition of a water-permeable non-light-sensitive layer, which is in direct contact with the light-sensitive silver halide emulsion layer, or they may be incorporated into a non-light-sensitive layer, which is separated from the light-sensitive layer by a water-permeable non-light-sensitive layer.

Thus, a photographic element according to the present invention which is suitable for use in the process of the above U.S. Pat. specification for the production of direct positive color images comprises a. at least one water-permeable layer containing light-sensitive silver halide grains,

b. a color coupler in effective contact with said silver halide grains, said coupler being capable of forming on color development a dye, which by treatment with a strong acidic solution can be converted into colorless products, and

c. in efi'ective contact with said color coupler a quinolone hydrazone compound which corresponds to the above general formula and which is capable of forming an acid-resistant cyan dye by oxidative coupling with said color coupler.

By effective contact of the color coupler with the silver halide" is to be understood that the oxidized developing agent formed by the reduction of the exposed silver halide can come into contact with the color coupler in order to react therewith at the exposed areas.

By effective contact of the color coupler with the oxidatively coupling compound" is to be understood that the oxidatively coupling compound can oxidatively couple with the color coupler in the colloid layer wherein the latter is present on treatment in oxidative medium.

In accordance with the present invention the photographic element for producing direct positive color images comprises more specifically at least one water-permeable colloid layer wherein light-sensitive silver halide grains are present and wherein said water-permeable colloid layer or a colloid layer in water-permeable relationship therewith comprises at least one color coupler which on development couples in the exposed areas with the oxidation product of an aromatic primary amino developing agent to form on these areas a dye which can be destroyed or transformed into colorless products by treatment with a strong acidic solution, and wherein the said water-permeable colloid layer containing the silver halide or a colloid layer in water-permeable relationship therewith contains a quinolone hydrazone compound corresponding to the above general formula, which on treatment of the color developed photographic element in an oxidizing solution oxidatively couples with said color coupler to form in the nondeveloped areas a secondary cyan dye which cannot be destroyed or transformed into colorless products by the said treatment with a strong acidic solution.

The quinolone hydrazone oxidatively coupling compounds described in the present invention are usually incorporated into a red-sensitive silver halide emulsion forming one of the difierently sensitized silver halide emulsion layers of a photographic multilayer color material suitable for producing a direct positive multicolor image according to the method of the above U.S. Pat. specification. A photographic multilayer material according to the present invention therefore comprises a support, a red-sensitized silver halide emulsion layer, a green-sensitized silver halide emulsion layer, and a blue-sensitive silver halide emulsion layer each of said emulsion layers containing a color coupler capable of forming on development a quinone-imine or azomethine dye and an oxidatively coupling compound which, after development, on treatment with an oxidative bleaching bath, reacts with the residual color coupler so as to form an acid-resisting cyan, magenta, and yellow dye respectively wherein the oxidatively coupling compound of the red-sensitive emulsion layer is a hydrazone com pound corresponding to the above general formula.

The color couplers and oxidatively coupling compounds can of course be present not only in their respective light-sensitive silver halide emulsion layers but also in adjacent nonlight-sensitive colloid layers.

In the above U.S. Pat. No. 3,293,032 which should be read in conjunction with the present invention more details can be found as regards the appropriate color couplers and oxidatively coupling compounds for forming the yellow and magenta direct positive separation images in addition to the cyan direct positive separation image formed in accordance with the present invention by means of the oxidatively coupling compounds corresponding to the above general formula.

According to a preferred embodiment of the present invention for forming with a multilayer material as described above direct positive multicolor images the yellow separation image is formed by oxidative coupling of a pyrazolone color coupler with a benzothiazolone hydrazone coupling compound, the magenta separation image is formed by oxidative coupling of an a-naphthol color coupler with a 4-amino-pyrazolone-3 coupling compound and the cyan separation image is formed by oxidative coupling of an a-naphthol color coupler with a quinolone hydrazone coupling compound according to the present invention. The a-naphthol color coupler used for the formation of the magenta separation image may be the same as that used for the formation of the cyan separation image.

As described in the above U.S. Pat. specification the ratio in moles of light-sensitive silver halide to color coupler is preferably comprised between 6:] and 15:1 and the ratio of color coupler to oxidatively coupling compound preferably varies from 1:1 to 1:3.

The color couplers and oxidatively coupling compounds can be incorporated into the photographic material according to any technique known .by those skilled in the art for incorporation of photographic ingredients, more particularly color couplers and mask-forming compounds, into colloid compositions. For instance, the water-soluble compounds can be incorporated into the coating composition of the layer in question from an aqueous solution or alkaline aqueous solution and the water-insoluble or insufficiently water-soluble compounds from a solution in the appropriate water-miscible or water-immiscible high-boiling or low-boiling organic solvents or mixtures thereof whereupon the solution obtained is dispersed, if necessary in the presence of a wetting or dispersing agent, in a hydrophilic colloid composition forming or forming part of the binding agent of the colloid layer. The hydrophilic colloid composition may of course comprise in addition to the colloid carrier all other sorts of ingredients.

The solutions of the color couplers and oxidatively coupling compounds need not necessarily be dispersed or dissolved directly in the coating composition of the silver halide emulsion layer or other water-permeable layer. Said solution may advantageously be first dispersed or dissolved in an aqueous non-lightosensitive hydrophilic colloid solution whereupon the resultant mixture, if necessary after the removal of the organic solvents employed, is intimately mixed with the said coating composition of the light-sensitive silver halide emulsion layer or other water-permeable layer just before coating.

For more details about particularly suitable techniques that can be employed for incorporating the color couplers and oxidatively coupling compounds into a hydrophilic colloid layer of a photographic material there can be referred to United Kingdom Pat. Nos. 791,219, 1,098,594, 1,099,414, 1,099,415, 1,099,416, 1,099,417, to Belgian Pat. Nos. 705,889, 722,026, to U.S. Pat. application Ser. No. 856,825 and to U.S. Pat. No. 2,304,940.

The hydrophilic colloid used as the vehicle for the silver halide may be, for example, gelatin, colloidal albumin, zein, casein, a cellulose derivative, a synthetic hydrophilic colloid such as polyvinyl-alcohol, poly-N-vinylpyrrolidone etc. If desired, compatible mixtures of two or more of these colloids may be employed for dispersing the silver halide.

Various silver salts may be used as the sensitive salt, such as silver bromide, silver iodide, silver chloride, or mixed silver halides, such as silver chlorobromide, silver bromoiodide and silver chlorobromoiodide.

Though for the formation of direct positive images according to the present invention, a photographic element comprising differently sensitized silver halide emulsion layers each containing a color coupler and an oxidatively coupling compound, is preferably used, photographic materials can be used containing mixed packet photographic silver halide emulsions. For further details as regards this kind of emulsions there can be referred to the above U.S. Pat. No. 3,293,032 and the patent literature referred to therein.

The light-sensitive silver halide emulsions of use in the preparation of a photographic material according to the present invention may be chemically as well as optically sensitized. They may be chemically sensitized by effecting the ripening in the presence of amounts of sulphur containing compounds such as allyl thiocyanate, allyl thiourea, sodium thiosulphate, etc. The emulsions may also be sensitized by means of reductors for instance tin compounds as described in French Pat. No. 1,146,955 and in Belgian Pat. No. 568,687, imino-amino methane sulphinic acid compounds as described in United Kingdom Pat. No. 789,823 and small amounts of noble metal compounds such as of gold, platinum, palladium, iridium, ruthenium and rhodium. They may be optically sensitized by means of cyanine and merocyanine dyes.

The said emulsions may also comprise compounds which sensitized the emulsions by development acceleration for example compounds of the polyoxyalkylene type such as alkylene oxide condensation products as described among others in U.S. Pat. Nos. 2,531,832 and 2,533,990, in United Kingdom Pat. No. 920,637, 940,051, 945,340 and 991,608 and in Belgian Pat. No. 648,710 and onium derivatives of amino-N-oxides as described in United Kingdom Pat. No. 1,121,696. Further, the emulsions may be stabilized with heterocyclic nitrogen-containing thioxo compounds such as benzothiazoline-Z-thione and 1-phenyl2-tetrazoline-5-thione and compounds of the hydroxy-triazolo-pyrimidine type. They can also be stabilized with mercury compounds such as the mercury compounds described in Belgian Pat. Nos. 524,121, 677,337, 707,386 and in U.S. Pat. No. 3,179,520,

The light-sensitive emulsions may also comprise all other kinds of ingredients such as plasticizers, hardening agents, wetting agents, etc.

The emulsions can be coated on a wide variety of photographic emulsion supports. Typical supports include cellulose ester film, polyvinylacetal film, polystyrene film, polyethylene terephthalate film, and related films of resinous materials, as well as paper and glass.

In accordance with the present invention photographic direct positive cyan images are produced by the steps of:

1. imagewise exposing a photographic element comprising a. at least one water-permeable layer which contains lightsensitive silver halide grains,

b. a color coupler in efiective contact with said silver halide grains, said coupler being capable of forming on development a dye which by treatment with a strong acidic solution can be transformed in colorless products, and

c. in effective contact with said color coupler a quinolone hydrazone compound corresponding to the above general formula, said compound being capable of forming an acid-resistant cyan dye by oxidative coupling with said color coupler,

2. developing the photographic element in a color-forming developer,

3. treating the photographic .element in an oxidative bleaching bath,

4. treating the photographic element in a strong acidic solution, and

5. fixing the photographic element no later than after said step (4), but not before said step 2).

The strong acidic solution which causes the destruction of the non-acidresistant primary dye formed on color development at the exposed areas is an acidic solution the pH of which is preferably at least 1 i.e. an acidic solution the hydrogen ion concentration of which is preferably at least 1 i.e. an acidic solution the hydrogen ion concentration of which is preferably at least 10" gram equivalent per liter.

According to a preferred embodiment for preparing direct positive multicolor images according to this invention, this process comprises the steps of imagewise exposing a photographic element comprising a red-sensitive, a green-sensitive and a blue-sensitive silver halide emulsion layer each of said layers containing a color coupler capable of forming on development a dye which by treatment with a strong acidic solution can be transformed into colorless products, the bluesensitive and green-sensitive layers also containing compounds capable of forming acid-resistant yellow and magenta dyes respectively by oxidative coupling with the color couplers present in the said layers and the red-sensitive layer also containing a quinolone hydrazone compound corresponding to the above general formula and capable of forming an acid-resistant cyan dye by oxidative coupling with the color coupler present in the red-sensitive layer, developing the photographic element in a color-forming developer, treating the photographic element in an oxidative bleaching bath, occasionally fixing the photographic element, treating the photographic element in a strong acidic solution containing at least one reducing agent or oxidizing agent, fixing the photographic element if not fixed before the acid treatment, finally rinsing and drying the photographic element whereby a positive color image is formed consisting of superposed cyan, magenta and yellow dye separation images which are built up in the photo- L5. graphic element by the dyes formed on oxidatively coupling by treatment with the oxidative bleaching solution.

For further details as regards suitable color-developing agents, the oxidative bleaching bath, the acid treatment, etc. there can be referred to the above US. Pat. specification which should be read in conjunction with the present invention.

The following examples illustrate the present invention.

Example 1 To a light-sensitive silver bromoiodide emulsion containing 4.5 mole percent of silver iodide are added per 150 millimole of silver halide:

Eighteen millimole of a 1 percent solution in ethanol of a sensitizing agent for red light having the following structural formula:

8.5 millimole of the color coupler N-(2-methyl-n-hexadecylamino- 5 '-sulphophenyl)- l hydroxy-2-naphthoic acid amide sodium salt from a 10 percent solution in a mixture of diacetone alcohol and water (1:4) occasionally comprising some alkali to promote dissolution, and

after neutralization of the emulsion: l0 millimole of the 0xp I a ldatlvely coupling compound 1 of the above list from a 10 percent solution in 0.2 N sodium hydroxide.

After the addition of the common emulsion additives such as wetting agent, hardener and stabilizer the emulsion is coated on a support and dried, 3 5

The light-sensitive material is imagewise exposed to an original and then processed at 20' C. in the following baths:

l developing bath (8 min.) having the following composition:

sodium hexametaphosphate 2 g. potassium bromide 0.5 g hydroxylamine hydrochloride l gv anhydrous sodium carbonate 30 g. sodium sulfite 2 g. Nethyl-Nsulphopropyl-p-phenylenediamine 6 g. water to make 1 liter 2. Intermediate bath (4 min.) having the following composition:

borax sodium hydroxide necessary to obtain pH l0.l water to make 1 liter 3. bleach bath (2 min.) having the following composition:

7. rinsing bath (6 min. I

The total processing lasts about 34 min. A positive cyan image of high density is obtained. The absorption maximum of the dye lies at 660 nm.

Example 2 Example 3 in an analogous way as described in example I, the oxidatively coupling compound 1 of the above table is incorporated in a silver bromoiodide emulsion together with one of the anaphthylsulphamoyl or m-acylamino-N,N-diethylaniline color couplers given above.

After exposure and processing as described in example I, cyan images are produced the absorption maxima of which are as follows.

Color coupler Absorption maximum (nm.)

Example 4 A photographic multilayer material is used for preparing direct positive color images. This multilayer material consists of the following superposed layers in the indicated sequence: a support, an antihalation layer, a red-sensitive silver halide emulsion layer, a gelatin interlayer, a green-sensitive silver halide emulsion layer, a yellow filter layer, a blue-sensitive silver halide emulsion layer and a gelatin antistress layer.

The red-sensitive emulsion layer has the composition given in example 1.

The gelatin interlayer may comprise a magenta to magentared colored dyestuff as screening dye.

The green-sensitive emulsion layer is prepared as follows:

To a light-sensitive silver bromoiodide emulsion containing 4 mole percent of silver iodide are added per millimole of silver halide:

twenty millimole of a 1 percent alcoholic solution of the following sensitizers:

( zh-SO -NH-CO-OH; 0,191,

V M?F JPIBTEQQW@fiikiqis E twenty millimole of the color coupler N-(2'-n-hexadecylsulphonyl-S '-sulphophenyl l hydroxy-2-naphthoic acid amide sodium salt from a percent solution in alcohol and water, and

17 millimole of the odixatively coupling compound 1- methyl-2-methyl-3-n-pentadecyl-4-amino-antipyrine monohydrochloride from a 10 percent solution in ethanol.

After the addition of the usual additives such as hardeners, stabilizers and wetting agents the emulsion is coated.

The yellow filter layer may comprise colloidal silver or organic yellow dyes.

The blue-sensitive silver halide emulsion layer is prepared as follows:

To a light-sensitive bromoiodide emulsion containing 3 mole percent of silver iodide are added per 150 millimole of silver halide:

fifteen millimole of the color coupler l-(3-sulpho-4- phenoxyphenyl)- 3-stearoylamino-pyrazolone-S from a 10 percent solution in alcohol-water 1:1 and fourteen millimole of the oxidatively coupling compound 1- methyl-6-sulphobenzothiazolone-Z(4'-n-hexadecylsulphonyl-3'-acetylaminophenyl)-sulphonyl hydrazone from a 10 percent solution of alkaline diacetone alcohol.

After adjustment of the pH to 7-8 the usual additives such as hardeners, wetting agents and stabilizers are added whereupon the emulsion is coated.

The multilayer material formed is exposed to a colored original and processed as described in example 1.

A positive color image of the original is obtained having brilliant colors and correct color rendition and having a high stability on storing under various circumstances of heat, light, and humidity.

The yellow, magenta and cyan separation images have absorption maxima: 440 nm., 540 nm. and 660 nm. respectively.

The improved absorption characteristics of the cyan images formed in accordance with the present invention as compared with the cyan images formed by the use of oxidatively coupling compounds described in U.S. Pat. No. 3,293,032 is clearly apparent from the density versus wavelength (nm) curves on FIGS. 1 and 2 of the accompanying drawings.

In FIG. 1 the absorption curves are given of the cyan dyes formed by oxidative coupling of the color coupler l of example 2, with oxidative coupling compound 1 according to the present invention (solid line curve) and with the oxidative coupling compound of preparation 7 of the above U.S. Pat. specification (dashline curve).

In FIG. 2 the absorption curves are given of the cyan dyes formed by oxidative coupling of the color coupler 2 of example 2 with oxidative coupling compound I according to the present invention (solid line curve) and with the oxidative coupling compound of preparation 7 of the above U.S. Pat. Specification (dashline curve).

We claim:

1. A photographic element comprising a quinolone hydrazone compound corresponding to the formula:

wherein:

Ar stands for an aryl group,

R, stands for an alkyl group, an aryl group, an aralkyl group,

or an amino group,

R stands for an alkyl group, and

M stands for hydrogen or an alkali metal atom.

2. A photographic element according to claim 1, wherein said element comprises at least one water-permeable lightsensitive silver halide layer, and a color coupler in effective contact with said silver halide and with the said quinolone hydrazone compound said color cougler being capable of forming on color development a dye, w ich by treatment with a strong acidic solution can be converted into colorless products, and of forming an acid-resistant cyan dye by oxidative coupling with the said quinolone hydrazone compound.

3. A photographic element according to claim 2, wherein the said color coupler and the said quinolone hydrazone compound are present in the said water-permeable light-sensitive silver halide layer or in a colloid layer in water-permeable relationship with said layer.

4. A photographic element according to claim 2, wherein said element is a multilayer color element comprising three silver halide emulsion layers which are differently spectrally sensitized of which a red-sensitized silver halide emulsion layer or a non-light-sensitive colloid layer in water-permeable relationship therewith comprises a color coupler capable of forming on development a quinone-imine or azomethine dye which can be destroyed or transformed into colorless products by treatment with a strong acidic solution and a said quinolone hydrazone compound which on treatment of the color developed photographic element in an oxidizing solution oxidatively couples with said colorless color coupler to form in the nondeveloped areas a cyan dye which cannot be destroyed or transformed into colorless products by the said treatment with a strong acidic solution.

5. A photographic element according to claim 2, wherein said color coupler is a color coupler of the a-naphthol type.

6. A photographic element according to claim 2, wherein said color coupler is a a-naphthylsulphamoyl color coupler.

7. A photographic element according to claim 2, wherein said color coupler is a m-acylamino-N,N-dialkylaniline color coupler.

8. Process for the production of direct-positive color images which comprises the steps of imagewise exposing a photographic element according to claim 2, developing the photographic element in a color forming developer, treating the photographic element in an oxidative bleaching bath, treating the photographic element in a strong acidic solution and fixing the photographic element no later than after the said acid treatment step but not before the said color development step, thus forming colorless reaction products at the exposed areas where development occurred, and a positive color image as a result of oxidative coupling at the unexposed areas.

9. Process according to claim 8, wherein the color-forming developer comprises a primary amino developing agent.

10. Process according to claim 8, wherein the oxidative beaching bath is an alkaline bleaching bath containing potassium hexacyanoferrate (III).

11. Process according to claim 8, wherein the strong acidic solution has a hydrogen ion concentration of at least 10 gram equivalent per liter.

12. Process according to claim 11, wherein the acidic solution also comprises an oxidizing agent or reducing agent. 

2. A photographic element according to claim 1, wherein said element comprises at least one water-permeable light-sensitive silver halide layer, and a color coupler in effective contact with said silver halide and with the said quinolone hydrazone compound, said color coupler being capable of forming on color development a dye, which by treatment with a strong acidic solution can be converted into colorless products, and of forming an acid-resistant cyan dye by oxidative coupling with the said quinolone hydrazone compound.
 3. A photographic element according to claim 2, wherein the said color coupler and the said quinolone hydrazone compound are present in the said water-permeable light-sensitive silver halide layer or in a colloid layer in water-permeable relationship with said layer.
 4. A photographic element according to claim 2, wherein said element is a multilayer color element comprising three silver halide emulsion layers which are differently spectrally sensitized of which a red-sensitized silver halide emulsion layer or a non-light-sensitive colloid layer in water-permeable relationship therewith comprises a color coupler capable of forming on development a quinone-imine or azomethine dye which can be destroyed or transformed into colorless products by treatment with a strong acidic solution and a said quinolone hydrazone compound which on treatment of the color developed photographic element in an oxidizing solution oxidatively couples with said colorless color coupler to form in the nondeveloped areas a cyan dye which cannot be destroyed or transformed into colorless products by the said treatment with a strong acidic solution.
 5. A photographic element according to claim 2, wherein said color coupler is a color coupler of the Alpha -naphthol type.
 6. A photographic element according to claim 2, wherein said color coupler is a Alpha -naphthylsulphamoyl color coupler.
 7. A photographic element according to claim 2, wherein said color coupler is a m-acylamino-N,N-dialkylaniline color coupler.
 8. Process for the production of direct-positive color images which comprises the steps of imagewise exposing a photographic element according to claim 2, developing the photographic element in a color forming developer, treating the photographic element in an oxidative bleaching bath, treating the photographic element in a strong acidic solution and fixing the photographic element no later than after the said acid treatment step but not before the said color development step, thus forming colorless reaction products at the exposed areas where development occurred, and a positive color image as a result of oxidative coupling at the unexposed areas.
 9. Process according to claim 8, wherein the color-forming developer comprises a primary amino developing agent.
 10. Process according to claim 8, wherein the oxidative beaching bath is an alkaline bleaching bath containing potassium hexacyanoferrate (III).
 11. Process according to claim 8, wherein the strong acidic solution has a hydrogen ion concentration of at least 10 1 gram equivalent per liter.
 12. Process according to claim 11, wherein the acidic solution also comprises an oxidizing agent or reducing agent. 